"The women were very excited, but for cultural reasons they could not share their discovery by going from village to village, but they did make a video to spread the word," said Holderness in a phone interview from Rome. "That video went all [a]round Bangladesh and eventually reached west Africa."

Holderness is executive secretary of the Global Forum on Agricultural Research (GFAR), which was established to shift the focus of agricultural research and development to meet the needs of the world's poor, the group most affected by the two big food crises in the past four years. Those crises were fuelled by several global trends: growing population, expanding incomes in emerging countries such as China and India, conversion of food crops to biofuels, and climate change.

The Montpellier meeting underlines the importance that G20 countries are putting on agriculture, especially in the developing world. G20 agriculture ministers held their first summit in Paris in June, where they agreed an action plan to deal with volatility in food prices. The focus of this week's meeting will be a bigger version of what Holderness experienced in Bangladesh.

The meeting will be opened by the French agriculture minister, Bruno Le Maire, who has made a big push for the importance of agriculture in the G20. Participants will include Tang Huajun, vice-president of the Chinese Academy of Agricultural Sciences, and Andrew Westby, director of the Natural Resources Institute in the UK.

The G20 group, consisting of the world's leading economies – including China and South Africa – is a powerhouse of both agricultural innovation and production, with around 70% of scientific publications on agriculture and around 60% of agricultural exports. The G20 also leads in areas such as information and communication technologies, which can change the way agricultural knowledge is made available.

But with an alphabet soup of organisations involved in agricultural research at national and international level, developing a coherent approach, setting out priorities and fulfilling objectives is problematic. Montpellier has four specific objectives: increased co-operation and co-ordination of research policies and programmes on food security; effective and innovative research partnerships for development and better impact of research from the Consultative Group on International Agricultural Research; stronger capacities in agriculture technologies for poor countries and synergies between G20 agricultural research systems; and greater involvement of the G20 agricultural research systems in the second global conference on agricultural research for development (Gcard) in Uruguay in 2012.

Holderness said it was particularly important for poor countries to learn from the success of emerging economies such as China and Brazil.

"How do we spread the knowledge not just from China and Brazil but from suppliers, informational technology providers," he said. "Not just scientific knowledge, but innovations and practices that can be shared and made relevant to farmers. The core message of the meeting is that the G20 recognises the importance of agricultural research. It's good it's happening at all, but we are looking for not just more talk but action."

Montpellier will feed into the G20 joint finance/development meeting in September in Washington and the G20 summit in Cannes in November. Success can only be measured in tangible effects on the ground. In their discussions on food security and self-reliance, ministers should be asking themselves what impact they will have on a woman farmer in Kenya with a few acres, who is struggling to grow crops on semi-arid soil to feed her family and generate income for school revenues.

Farmers like her are keen to embrace innovations such as zai pits, which hold fertiliser and water to help crops grow, because they have seen how these can increase yields of drought-resistance crops such as cowpeas, pigeon peas and sorghum. But they face very basic challenges. How do they afford to buy a hoe that costs $70, or transport their crops to market?

"We need to look at innovation in a broader social context," Holderness said. "We have to bring in women at the start – there is access to microfinance, access to water for sharing, schemes for producers to organise themselves for access to markets. The technology is essential but not sufficient in itself."